Wireless bi-directional or unidirectional streaming of audio data between a pair of hearing instruments, or a hearing instrument and another portable communication device, is highly desirable. There exists, however, a number of technical problems in terms of power consumption, reliability, transmission latency or delay, component size etc. with prior art wireless data communication methodologies, protocols and devices that must be addressed to deliver a feasible solution for a hearing instrument due to the small amount of power available from typical batteries of hearing instruments.
Standardized wireless data communication protocols such as Bluetooth LE as defined by the Bluetooth Core Specification 4.1, or earlier versions, does not allow for real-time audio transport. There are a number of limitations in the protocol as defined that means that real-time audio transport is unfeasible without changing certain protocol layers:                The nature of the L2CAP channels as defined for LE—where a best effort approach for data transport with no timeouts or flushes on transmissions is defined—also means that it is next to impossible to do a real-time audio service over LE as defined.        The lack of real-time transport means also means that stereo synchronization between two paired audio sinks (such as hearing aids) is next to impossible.        The packet size means that the overhead data for transmitting the required data rate for real-time audio (typically 16-96 kbit/s) is very high.        
It is an object of the present method of exchanging data packages between the first and second portable communication devices to overcome the above-mentioned problems and shortcomings of the prior art wireless data communication methodologies, protocols and devices.